Exclusive: Former FSA chief Tim Smith understood to have warned Department of Health that revealing food poisoning contamination rates could provoke a food scare and damage the industry.

The former head of the Food Standards Agency (FSA), who went straight from his job as regulator to a lucrative role as technical director of Tesco, lobbied the government this summer about its plans to publish the official food poisoning contamination rates for supermarket chicken, the Guardian has been told.

Tim Smith is understood to have warned the Department of Health in June that FSA proposals for publishing results, which included naming and shaming individual supermarkets, could provoke a food scare and damage the industry.

Tim Smith, technical director of Tesco. Photograph: Anna Gordon

The lobbying has raised questions over whether Smith has abided by terms set by David Cameron for his appointment. His move straight from the regulator to a supermarket group he had been regulating in October 2012 was approved by the prime minister, following advice from the Advisory Committee on Business Appointments, on the condition that he did not lobby civil servants or ministers on behalf of Tesco for two years.

The FSA has been fighting a decade-long campaign to get supermarkets and the poultry industry to clean up their meat. A Guardian investigation into industry hygiene lapses earlier this year revealed that the majority of fresh supermarket chicken remains contaminated with the potentially lethal food poisoning bug campylobacter. Six in ten chickens were contaminated in anonymised FSA tests results released after a delay in August. The industry is now poised to receive the results of further tests covering peak season for the bug, due to be published on Thursday. These are likely to show even higher rates of contamination and will identify individual supermarkets and their scores.

The policy of naming and shaming the dirtiest companies for their campylobacter rates has been a key part of the FSA’s strategy to deal with industry’s failure to tackle what is the commonest form of food poisoning in the UK – it kills around 100 people and makes an estimated 280,000 sick each year.

However the agency backed down in July from its public promise to name individual retailers in the first batch of contamination results. It had come under intense pressure from other government departments, and according to sources, Number 10 had raised concerns that the communication of results could provoke a food scare similar to that triggered when former conservative minister Edwina Currie warned that most British eggs were contaminated with salmonella in 1988.

The FSA said in the summer when it decided to back down from naming supermarkets that “other government departments have reflected to us concerns which are the same as those we’ve heard directly from retailers and producers”.

Now it is alleged that the FSA’s own former boss appeared to undermine its campylobacter strategy. Labour’s food and farming minister Huw Irranca-Davies wrote earlier this month to the health secretary Jeremy Hunt asking for “unequivocal assurance” that Smith did not lobby his department inappropriately over campylobacter and in breach of his conditions of appointment, but has not yet received a reply.

Despite the conditions attached to his appointment, The Guardian has been told that Smith approached the senior civil servant responsible for the Department of Health’s public health division for a discussion about the publication of the campylobacter results. During the conversation he is said to have raised concerns that it would provoke a food scare.

The Guardian put in Freedom of Information requests to the department last month, asking which companies lobbied over campylobacter and what had passed between the departments. The department refused to give any information and that decision is now being appealed.

The Guardian also asked the department last week if its public health team had been lobbied by Smith. A spokeswoman said it could not comment because of the FoI appeal.

Both Tesco and Smith declined to say whether he had lobbied on the supermarket’s behalf in apparent breach of the conditions of his appointment. In a statement, Tesco said that it is “committed to the reduction of the industry-wide issue of campylobacter in poultry”.

“We work in close collaboration with our suppliers, other retailers and relevant food and health authorities to address the issue at all stages of the supply chain.”

Asked whether it had been made aware by DH of any views expressed by Smith on campylobacter results, the FSA said it could not comment as the content of exchanges between departments on campylobacter strategy was part of a separate FoI request by the Guardian which had been refused.

The agency is still being lobbied by industry in a last-ditch attempt to stop it naming and shaming individual companies in this week’s results.

The current FSA chief executive, Catherine Brown, noted in board papers this month: “It is disappointing that the British Retail Consortium, which speaks on behalf of retailers, has written to us again pressing us not to release the results of the retail survey and seeking to call in to question the validity of the sampling plan, which they were consulted about before the survey commenced.”

Irranca-Davies said; “To tackle campylobacter we need transparency on the extent of the problem. We also need transparency whether there has been any inappropriate lobbying to delay or dilute publication of the campylobacter rates.

“After the horsemeat scandal and the allegations of hygiene failings in the poultry industry the government must restore confidence in the food sector and ensure that the FSA puts the interests of the consumer first.”

Which? executive director Richard Lloyd, said: “It’s scandalous that so much chicken with high levels of campylobacter ends up on our supermarket shelves.

“The supermarkets, watchdog and industry need to clean up their act and immediately publish the data they’ve been keeping from the public and tell consumers what action they’re taking to make sure that chicken is safe.”

Campylobacter: at a glance

Campylobacter thrives in the gut and faeces of poultry, and can easily be spread from bird to bird on farms or in abattoirs. The bug is killed by cooking but it is also easily spread when raw meat contaminates surfaces and utensils in the kitchen. It is the most common cause of food poisoning in the UK, making around 280,000 people ill each year and leading to around 100 deaths. In rare cases it can cause serious disability. Since many people do not report food poisoning, the real figure for campylobacter illness are probably much higher. This year the Food Standards Agency reported that 59% of raw chicken on sale in the UK is contaminated with campylobacter. The FSA reveals new tests this week detailing the rates at different supermarkets.

To clean up the system would cost money. Intensive farming, cramped transport conditions, the mechanised processes in modern abattoirs have all contributed to higher rates of campylobacter. With constant pressure from supermarkets to keep the price of chicken low, and the industry working on high volumes but low margins, experts say the campylobacter problem has been left unsolved for years.